Thread roller feeding mechanism



June 13, 1967 w. s. REILEY 3,324,697

THREAD ROLLER FEEDING MECHANISM V Filed June 26, 1964 2 Sheets-Sheet 1 FIG.

'INVENTOR. WILLIAM s. REILEY BMW,

ATTORNEYS June 13, 1967 w. s. REILEY 3,324,697

' THREAD ROLLER FEEDING MECHANISM Filed June 26, 1964 2 Sheets-Sheet 2 INVENTOR. WILLIAM S. REILEY ATTORNEYS United States Patent 3,324,697 THREAD ROLLER FEEDING MECHANISM William S. Reiiey, Simshury, Conn., assignor to The Hartford Special Machinery Company, Simsbury, Conn., a corporation of Connecticut Filed June 26, 1964, Ser. No. 378,123 3 Claims. (CI. 7290) This invention generally relates to devices for feeding objects to a work station, and is more particularly directed to the provision of improved apparatus particularly suited for feeding headed blanks in thread rolling machines.

It is a primary object of this invention to provide a high speed thread roller having an improved work blank feeding mechanism that reliably delivers work blanks to the thread rolling dies in a rapid manner wit-h the blank properly positioned for the thread rolling operation.

It is also a primary object of this invention to provide an improved feeding mechanism which continuously delivers work blanks in a controlled manner and at high delivery rates.

It is a still further object of this invention to provide an improved feeding device which assists the transfer of the workpiece to the work station.

It is a still further object of this invention to provide an improved work blank feeding device particularly useful with thread rollers that is economically manufactured and easily installed as an accessory to provide high speed, reliable delivery of properly oriented work blanks.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application which will be indicated in the appended claims.

In the drawings:

FIG. 1 is a fragmentary top plan view partially in cross section of a thread rolling machine incorporating the improved feeding mechanism of this invention;

FIG. 2 is a fragmentary side elevation view taken generally along the lines 22 of FIG. 1 with the track cover mechanism shown in dotted lines; and

FIG. 3 is a fragmentary elevation view with a portion of the feed drum removed to show the upper terminus of the feeding mechanism.

For illustrative purposes, the present invention is shown installed on portions of a thread rolling machine of the type disclosed in US. Patent No. 3,117,473, entitled, Thread Rolling Machine and assigned to the assignee of the present invention. The machine 10 incorporates a screw blank feeding device generally designated 12 which conducts the blanks 13 from the rotatable drum or hopper 14 to the thread forming portion of the machine which includes a fixed die 16 that is secured to the bed 17 of the machine by a clamp 18 and a reciprocating or movable die 20 which is driven by any suitable mechanism (such as that shown in US. Patent No. 3,117,473) so as to reciprocate in a direction parallel to fixed die 16. A suitable clamp 21 secures the die 20 to a movable carriage or slide and a movable combination gate and starter finger 25 of the type also shown in the aforementioned patent is provided between the dies 16 and 20 to control the discharge of screw blanks 13 from feeding mechanism 12 and to wedge the blanks between the dies at the commencement of each thread rolling operation. FIGS. 1 and 2 show the dies 16 and 29 at the beginning of the thread forming operation on blank 26 which was positioned by finger 25 after being discharged from feeding mechanism 12 by movement of the finger 25 to the position shown by the dotted line 25A.

3,324,697 Patented June 13, 1967 The feeding device 12 includes a pair of parallel feed rails 27, 28 which extend from a position within the drum 14 (see FIG. 3) to a lower terminal point which is adjacent the leading edge of the fixed die 16, the rails being spaced by an amount sufficient to receive shank portion 30 of each blank while supporting the head portion 31 of each blank. In FIG. 1 the lower end of rail 27 and the blanks adjacent thereto are shown in cross section to facilitate description of certain aspects of the invention. For completeness, a track cover mechanism of the type shown in copending US. patent application Ser. No. 267,717 now abandoned and assigned to the assignee of the present invention is disclosed in dotted lines as including a main cover portion 35 and a movable extension cover portion 36 pivotally secured at 32 and provided with a latch mechanism 33 controlled by handle 34 to permit pivoting of the cover extension 36 away from the rails to permit easy removal of malformed work blanks. For further details of the thread rolling machine itself and the preferred track cover, reference is made to the above identified patent and patent application.

As the speed of operation illustrated on the thread rolling machine is increased, the time available for proper positioning of a work blank at leading edges of the dies is decreased. For example, operation of the machine of US. Patent No. 3,117,473 at speeds of approximately 400 strokes of the movable die per minute allow approximately .01 second for movement of a work blank from its position at the end of the feed rails to its position at the starting edge of the dies. At speeds of 800 strokes per minute, the gate at the end of the feed rails is open approximately /2 the aforementioned time; i.e., .005 second thereby making work blank feeding and positioning an important requirement if the number of workpieces to be produced is to be equal to the number of strokes of the movable die. Normal variances in work blank configuration as Well as normal wear and tear causes the screw production rate of a typical machine to be substantially less than the actual number of strokes per minute of the movable die.

In accordance with the present invention, improvement have been made to the feeding mechanism so as to insure a constant flow of properly oriented workblanks down the feed rails and proper discharge of the work blanks from the lower terminus of the feed rails. Turning first to FIGS. 1 and 2, a preferred embodiment of the work blank discharging mechanism is shown as being positioned at the discharge end of the feed rails 27, 28 and as including an air jet generally designated 40 including a passageway 41 extending'through feed rail 27 and terminating in air jet aperture 42, the air being supplied from any suitable source through tubing 44. The aperture 42 of air jet 40 is positioned in feed rail 27 to discharge air from a location in back of lowermost work blank 45 as its shank portion rests against the gatestarter finger 25, the air being directed so as to engage the shank portion of the blank in the preferred embodiment thereby to urge the blank out from between the feed rails. Additionally the passageway 41 is positioned at an acute angle relative to the work blank engaging face of the rail 27, such angle being approximately 30 in the preferred embodiment so as to direct the major portion of the air stream along the direction of feed while providing a component of pneumatic force extending transversely to the direction of feed.

With the feed rails inclined relative to the horizontal, the work blanks are gravity fed to the position shown in FIG. 2 with the heads of the blanks in edge to edge engagement. When the gate-starter finger 25 is moved in the direction of the arrow 50 (as the movable die 20 is moved to its fully retracted position), to reach its fully retracted position (shown at dotted lines 25A), the gravity force and the force exerted by air emitted from jet 42 combine to force the work blank out from between the rails 27, 28 into abut-ting engagement with the movable die. Theadditional force exerted on'the work blank'by the jet of air reliably'insures that each time the gate 25 opens and closes a work blank will be discharged into proper position for the thread rolling operation.

A further. advantage of the'air jet which can be called an air escapement is obtained by providing a component of pneumatic force which is directed transversely of the feed rails. Because the work blanks are in head to head engagementon an inclined track, the work blank being transferred tends to tilt, such tilting being partially caused by the next adjacent work blank. However, the component of pneumatic force extending transversely to the pneumatic feed rails tends to retard the second blank upon opening of the gate 25, thereby introducing a slight spacing between the blank being transferred and the next adjacent blank so as to eliminate tilting force exerted by the second blank so as to insure proper seating of the transferredblankagainst the movable die.

Reliable high speed operation of a machine such as a thread roller also requires that the feed rails be kept filled with properly oriented work blanks which move smoothly to the discharge end. The present invention in feeding apparatus comprehends the provision of improvements at the upper or starting end of the feed rails to increase the reliability of delivery of blanks to the discharge end of the rails.

As .most clearly seen in FIG. 3, a drum or hopper 14 is supported for rotation in any suitable manner such as that shown in Patent No. 3,117,473 and provided with internal vanes (not shown) which lift work blanks from the bottom ofthe drum to let them tumble from the top of the drum as generally indicated by the blanks 60. As these blanks fall towards the bottom of the drum, they engage plate 61 which is inclined to-the horizontal to permit blanks which impinge thereon to slide towards the inclined feed rails 27, 28. Because these blanks engage the rails in a random fashion,- only a portion of blanks which reachthe. rails will be properly oriented so that the shank drops between the rails with the head properly resting thereon. Under normal conditions some of the blankswillbe oriented head first as with blank 63 so as.

to assume a position transverse to the feed rails as with blank 64. Similarly, certain of the blanks may have their head portion resting on the preceding blank as at 65 or may be deposited. on a portion of the feed rail already filled with blanks as with blanks 60A and. 60B. Such work blank conditions tend to create a jam atthe exit slot 68 and may permit improperly oriented blanks to proceeddown the feed rails.

In accordance with this invention, air jets are provided adjacent theexitpoint of the drum which jets have been arbitrarily designated the knock-oif jet 70 and the clearing jet 71. The clearing jet 71 continuously directs a stream of air into exit aperture 68 of the drum and at an angle above the feed rails so as to dislodge any improperly oriented blanks which would otherwise clog the drum exit. The knock-off jet 70 continuously directs a jet of air across the top surface of the feed rails so as to remove from the feed rails any blanks which may be extending transversely of the rails and to settle blanks which are (as with blank not properly seated on the feed rails.

The foregoing arrangement has been found to effectively provide a continuous row of properly oriented work blanks to the aforementioned air escapement so as to coact therewith in providing the improved feeding mechanism of this invention.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.

I claim:

1. Apparatus for feeding headed objects comprising a pair of feed rails for conducting the headed objects from the inlet end of the rails to the discharge end of the rails, a movable gate member extending across the discharge end of the feed rails, and means for effecting high speed discharge of the first headedobject from the discharge end of the rails while retarding the second headed object, said means comprising a jet of air directed against the shank portion of the headed object positioned adjacent the gate.

-2. The apparatus as set forth in claim 1 wherein said jet of air includes an orifice positioned in one of the feed rails adjacent the discharge end, said orifice being positioned to direct air toward the discharge endat an acute angle relative to the feed rail.

3. The apparatus as set forth in claim 1 wherein said air jet is directed against the shank portion toward a position adjacent the head of the headed object positioned adjacent the. gate.

References Cited UNITED STATES PATENTS 565,074 8/1896 Goddu 227-112 2,384,738 9/1945 Harvey 221-278 2,445,674 7/ 1948 Kendall 227-1 12 2,596,962 5/1962 Stern 729O 3,212,620 10/1965 Adams et a1 221278 CHARLES W. LANHAM, Primary Examiner.

H. D. HOINKES, Assistant Examiner. 

1. APPARATUS FOR FEEDING HEADED OBJECTS COMPRISING A PAIR OF FEED RAILS FOR CONDUCTING THE HEADED OBJECTS FROM THE INLET END OF THE RAILS TO THE DISCHARGE END OF THE RAILS, A MOVABLE GATE MEMBER EXTENDING ACROSS THE DISCHARGE END OF THE FEED RAILS, AND MEANS FOR EFFECTING HIGH SPEED DISCHARGE OF THE FIRST HEADED OBJECT FROM THE DISCHARGE END OF THE RAILS WHILE RETARDING THE SECOND HEADED OBJECT, SAID MEANS COMPRISING A JET OF AIR DIRECTED AGAINST THE SHANK PORTION OF THE HEADED OBJECT POSITIONED ADJACENT THE GATE. 